Flopped low str8 --> fast play?

[fretelöo]

The table is in the process of filling up (FR). Several players are waiting to post and the table is still quite loose. Given that I can be outdrawn rather easily on this semi-connected flop, is a raise in order?

Cryptologic
Limit Holdem Ring game
Limit: $2/$4
7 players
Converter

Pre-flop: (7 players) Hero is Button with 9[img]/images/graemlins/heart.gif[/img] 7[img]/images/graemlins/heart.gif[/img]
UTG calls, UTG+1 calls, MP1 calls, CO folds, Hero calls, SB folds, BB checks.

Flop: T[img]/images/graemlins/spade.gif[/img] J[img]/images/graemlins/diamond.gif[/img] 8[img]/images/graemlins/club.gif[/img] (5.5SB, 5 players)
BB checks, UTG checks, UTG+1 checks, <font color="#cc0000">MP1 bets</font>, Hero ???